The Stovebolt Site Forums The Shop Area Engine Shop '46 235 Fuel pump or ethanol or both?

1946 2Ton with 235 all stock original. I've had this truck for 15 years or so and have always run regular pump gas, which for some time here has been E-10. No issues. If I shut her down hot I'd notice some mild boiling of fuel in the glass bowl but it would only go down half way or so and then quit -- truck restarted hot reasonably so long as I held the throttle 1/4 open or so and did not pump the accelerator at all. Then came this summer -- bowl will boil all the way dry and even when running (and hot) the fuel pump will only sputter fuel into the bowl and keep it, maybe, 1/4 full at idle. She'll starve for fuel at prolonged red lights and she never did that before. I swapped the fuel pump out for a spare but no real improvement. Pulled the flex line off the bottom of the fuel tank and looked down the inside -- all OK there. put it back on and opened the petcock and fuel runs freely so that's good. Blew out steel line from tank/flex line to pump and that's OK.

1) Seems like the boiling point of the fuel is just low. Maybe I got a load of fuel with higher than spec ethanol?
2) I hear a lot of problems with bad out of the box fuel pumps. Thoughts in my case?

I'm reluctant to add insulation around lines, etc. as I'm an originalist -- also the truck did fine for years and nothing regarding the physical setup has changed. The only non-ethanol fuel available here is also high-octane (93 - 95) Is that any better from a boiling point perspective? OK to run in an old 235?

Thanks in advance?

Pete P.
Harborcreek, Penna.

High octane fuel burns more slowly than regular- - - -sort of like running slow-burning smokeless powder in a "magnum" rifle with a long barrel. It's not really needed or useful in a low compression engine like a stovebolt. You're likely to see much higher temperatures in your exhaust system, as some of that high priced gas does some of its burning between the engine and the muffler, and the exhaust valves won't like it.

Try doing a pressure/volume/vacuum test on the fuel pump- - - - -I suspect that the inlet and outlet check valves in the pump have gone south. There are several places that are highly recommended by members here that will rebuild your pump with ethanol-friendly parts. Good luck!
Jerry

I can't remember if you've posted before about your fuel pump so maybe this will be repetitive.

If it is a brand new pump, I'm inclined to believe that the fuel pump is faulty. Modern fuel pumps for the 216 and 235 (and virtually every other old car) are all Chinese garbage.

See if you can locate an original pump or one re-manned 30 years ago or so and have it rebuilt.

Many people on this site, including me, have had this experience caused by the crummy pumps available today. In my case, two of them failed - one of them straight from the box. Since I had my original pump rebuilt by Then & Now Automotive, I have not had any problems in over 4000 miles.

By the way, I use 87 ethanol virtually exclusively and haven't encountered a problem here in 95+ degree Atlanta.

Test your pump's fuel pressure and its output. One or both is likely incorrect.